VansAirForceForums  
Home > VansAirForceForums

- POSTING RULES
- Donate yearly (please).
- Advertise in here!

- Today's Posts | Insert Pics

  #1  
Old 08-17-2013, 08:59 PM
Dorfie Dorfie is offline
 
Join Date: Aug 2009
Location: Lexington, KY
Posts: 454
Default Cab-O-Sil vs Flox

The plans call for Cab-O-Sil to join the outer and inner door shells. I have a lot of Flox but no Cab-O-Sil. I believe the latter makes a viscous mix that does not flow. Can I use a thick mixture of Flox? Different strengths when cured?
Thanks.
Johan
__________________
Dorfie
RV10 Flying, N245JM
2020 dues paid with a smile
Reply With Quote
  #2  
Old 08-17-2013, 09:34 PM
9GT's Avatar
9GT 9GT is offline
 
Join Date: Jan 2010
Location: Southern Michigan
Posts: 1,966
Default

I used flox on my doors. Flox was used exclusively for structural joints building the Cozy MKIV so it was what I had on hand. After prepping the joint with 36 grit Zircon paper, clean up the dust and make sure everything is sanded,,,,no shinny spots. Paint both mating surfaces with a very light coat of pure mixed epoxy before applying the flox.
__________________
David C.
Howell, MI
RV-10: #41686 Under Construction
RV-9A: #90949 Under Construction
RV-10: #40637 Completed/Sold 2016
Cozy MKIV:#656 Completed/Sold 2007
"Donor Exempt" but donated through Dec. 2020
Reply With Quote
  #3  
Old 08-17-2013, 11:01 PM
Michael Burbidge Michael Burbidge is offline
 
Join Date: May 2006
Location: Sammamish, WA
Posts: 654
Default Zircon paper...

What is zircon paper? Is it special for sanding fiberglass?

Michael
__________________
Michael Burbidge
Sammamish, WA
RV-14A Empennage
RV-9A Flying?340 hours!
Last Donation: December 2019
Reply With Quote
  #4  
Old 08-17-2013, 11:56 PM
tfarrell839 tfarrell839 is offline
 
Join Date: Oct 2009
Location: Canby, OR
Posts: 53
Default Cab-o-sil is a thickener only

Cab o sil is silica. It's a thixotrphic agent. It's like the cornstarch of the epoxy world. You can add it up to 20% by volume. It adds no stregnth to the resin, but it also doesn't weaken it. Bonding the doors with Flox, with not too much flox in the mix, will cause the resin to thicken as well, and it is a stronger bond than just pure resin. I don't see a problem. You could also use a structural adhesive, such as some of the hysol products. Squeeze it well so you get a nice tight joint.
Reply With Quote
  #5  
Old 08-18-2013, 09:40 AM
mike newall's Avatar
mike newall mike newall is offline
 
Join Date: Jan 2005
Location: Yorkshire, England
Posts: 2,052
Default

Zircon only refers to a brand or type of grit paper.

It is basically 36 grit abrasive.

When doing the glass, I would always recommend a variety of coarse grit abrasives - mostly on long blocks.

Tip Time:

Make up the following -

18" x 3 x 3/4 MDF or good ply. Go to Home Despot or similar and look at belt sanding abrasive - it comes on a stout fabric backer.
Seal the MDF/ply with rattle can paint - nothing fancy, then use a branded contact adhesive to stick the fabric to the block.

I use 36/60 (double sided) on one block and 60/80 on the other block - never finer.......

If you are doing profiles, such as the canopy, use a piece of 4 x 2 around a foot long, profile one side using a plane to what you want the fillet to be and use 60 grit paper this time, again contact adhesive on.

Why so coarse ?

Because you are using it in a slow forward motion much like a file - the purpose is to remove material in an even manner, or to prep the surface as a good key to take adhesive, or epoxy.


If you are working towards a final surface, once you are close - then go in with finer grit paper to proceed towards a finish.
__________________
"I add a little excitement, a little spice to your lives, and all you do is complain!" - Q

Donated in 2020
Reply With Quote
  #6  
Old 08-18-2013, 06:09 PM
Michael Burbidge Michael Burbidge is offline
 
Join Date: May 2006
Location: Sammamish, WA
Posts: 654
Default Perfect timing...

The timing of this advice is perfect. I finished laying up my canopy fairing yesterday and am fretting how to remove enough fiberglass to get it to the appropriate shape. There is more fiberglass than I would like to remove, especially along the side of the fairing.

If I was to do the layup over again I would not wrap the first layers all the way around. (1/2 and 3/4 inch width pieces) This is because the curvature is flatter on the sides than on the front. So I have a bit of fiberglass to remove along the sides.

Michael-
__________________
Michael Burbidge
Sammamish, WA
RV-14A Empennage
RV-9A Flying?340 hours!
Last Donation: December 2019
Reply With Quote
  #7  
Old 08-18-2013, 08:58 PM
mike newall's Avatar
mike newall mike newall is offline
 
Join Date: Jan 2005
Location: Yorkshire, England
Posts: 2,052
Default

Michael,

If you need any further assistance, PM or email - we are all here to help

M
__________________
"I add a little excitement, a little spice to your lives, and all you do is complain!" - Q

Donated in 2020
Reply With Quote
  #8  
Old 08-19-2013, 01:39 PM
Dorfie Dorfie is offline
 
Join Date: Aug 2009
Location: Lexington, KY
Posts: 454
Default Thanks

Thanks for the responses. Flox it will be! If I mix flox to a thickness that it "does not pour" from the cup, is that thickness still OK? (Thats what the plans states for cab-o-sil use)
I got some ParaBeam (described as 3D FG) FG with the kit. It is much thicker, like two outer layers of FG with interconnecting fibers. It goes between the outer and inner door shells at two places each door. How do you wet these thicker pieces with resin? Will brush-on work? Submerge and squeeze access resin out?
Cheers.
Johan
__________________
Dorfie
RV10 Flying, N245JM
2020 dues paid with a smile
Reply With Quote
  #9  
Old 08-19-2013, 02:24 PM
Gary 40274 Gary 40274 is offline
 
Join Date: Dec 2007
Location: Conyers GA
Posts: 347
Default Wet vs Dry

One of the problems I have seen, is that folks get the resin cabosil mix either too wet of too dry. You want it wet enough so that it wets out on both surfaces of the door, but not so wet that it runs away from the bonding site. I suspect that most of the door flexibility problems stem from not getting a good bond between the two halves.

As far as wetting out the multi layer fiberglass, put it on a piece of poly sheet and wet it out with a stippling brush to get the correct resin/glass ratio. Then pick it up and place it in the desired location and stipple in place.

Gary Specketer Tech Counselor
Fiberglass guy
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 09:16 AM.


The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.